Method and system for image denoising using discrete total variation (TV) minimization with one-direction condition

摘要

A method of denoising an image, comprising the steps of a) initializing (S100) a direction index associated with each of image pixels, the direction index indicating an increase, a decrease and a mixed state in gradient direction of total variation at a given pixel, b) determining (S110) a discrete gradient of the total variation for each of the image pixels, the discrete gradient indicating the increase, the decrease or the mixed state, c) updating (S130) the direction index of each of the image pixels with the discrete gradient if the direction index is the mixed state, d) changing (S150) a pixel value of each of the image pixels by a predetermined value to reduce the total variation if the direction index and the discrete gradient are equal in the gradient direction for the one of the image pixels, and e) repeating (S160, S170) the steps b) through d) until a certain predetermined condition is reached.